Definition of gyroidal:
(adj) :
Spiral in arrangement or action.
(adj) :
Turning the plane of polarization circularly or spirally to the right or left.
(adj) :
Pertaining to a gyroid
(adj) :
(crystallography) Having the planes arranged spirally, so that they all incline to the right (or left) of a vertical line; said of certain hemihedral forms.